Lowry: The new climate deniers

This is an archived article that was published on sltrib.com in 2013, and information in the article may be outdated. It is provided only for personal research purposes and may not be reprinted.

There are few things sadder than the "climate denier." He ignores the data and neglects the latest science. His rhetoric and policy proposals are dangerously disconnected from reality. He can't recalibrate to take account of the latest evidence because, well, he's a denier.

The new climate deniers are the liberals who, despite their obsession with climate change, have managed to miss the biggest story in climate science, which is that there hasn't been any global warming for about a decade and a half.

"Over the past 15 years air temperatures at the Earth's surface have been flat while greenhouse-gas emissions have continued to soar," The Economist magazine writes. "The world added roughly 100 billion tons of carbon to the atmosphere between 2000 and 2010. That is about a quarter of all the CO2 put there by humanity since 1750." Yet, no more warming.

The Economist has been decidedly alarmist on global warming through the years, so it deserves credit for pausing to consider why the warming trend it expected to continue has mysteriously stalled out.

The deniers feel no such compunction. They speak as if it is still the late 1990s, when measurements of global temperature had been rising for two decades. In his State of the Union address, President Barack Obama said that "we can choose to believe in the overwhelming judgment of science and act before it's too late." In a passage devoted to global warming, though, he didn't mention the latest trend in global warming.

A denier feels the same righteous sense of certitude now, when warming has stopped, as he did a decade ago. Washington Post columnist Eugene Robinson recently opined that "sensible people accept the fact of warming"  but apparently not the fact of no-warming. He scorned those "who manipulate the data in transparently bogus ways to claim that warming has halted or even reversed course." Does he include James Hansen, the famous NASA scientist, among these dastardly manipulators? No one this side of Al Gore has warned as persistently about global warming as Hansen. He nonetheless admits that "the five-year mean global temperature has been flat for a decade."

None of this means that the Earth didn't get hotter in the 20th century, or that carbon emissions don't tend to create a warmer planet, or that warming won't necessarily begin again. It does mean that we know less about the fantastically complex global climate system than global-warming alarmists have been willing to admit. The Economist notes the work of Ed Hawkins of the University of Reading in Britain. He has found that if global temperatures stay the same for a few more years, they will fall below the range of 20 climate models. In other words, the scientific "consensus" will have been proven wrong.

Why the stall in warming? According to The Economist, maybe we've overestimated the warming impact of clouds. Or maybe some clouds cool instead of warm the planet. Or maybe the oceans are absorbing heat from the atmosphere. Although the surface temperature of the oceans hasn't been rising, perhaps the warming is happening deep down. James Hansen thinks new coal-fired plants in China and India, releasing so-called aerosols into the atmosphere that act to suppress warming, may be partly responsible for the stasis in temperatures.

Hansen writes that knowing more about the effect of aerosols on the climate "requires accurate knowledge of changes in aerosol amount, size distribution, absorption and vertical distribution on a global basis  as well as simultaneous data on changes in cloud properties to allow inference of the indirect aerosol forcing via induced cloud changes." Is that all? He ruefully notes that the launch of a satellite with a sensor to measure all of this failed, with no follow-up mission planned.

Hey, but don't worry. The science is all "settled."

What is beginning to seem more likely is that the "sensitivity" of the global climate to carbon emissions has been overestimated. If so, the deniers will be the last to admit it.